Black tetra(Gymnocorymbus ternetzi)

Very popular with many aquarists, this species is easy to maintain. However, take into account its restless behavior when it comes to finding it aquarium companions. More information later in this sheet

Scientific name

Gymnocorymbus ternetziTetragonopterus ternetziMoenkhausia ternetzi

Common name

Black tetraBlack widow tetra

Origin

Origin: Brazil, Colombia, ParaguayBiotope: Amazonian

Dimorphism

The smaller male with more contrasting colour

Group

Characidae

Volume

120 L / 26 imp gal / 32 US gal

Water parameters

T°: 24 to 28°C or 75 to 82°FpH: 6 to 7Hardness: 1 to 8°dGH

Difficulty

Easy

Size

5 to 6 cm (2 to 2.4")

Life expectancy

4 to 5 years

Living zone

Middle and depth

Individuals

10

Food

How to feed the Black tetra?

What kind of behavior does the Black tetra have?

It is a keen fish and a tireless swimmer. It is rather peaceful but can become shy or on the contrary become aggressive if it is kept in too few numbers. Like all species of the genus, it is gregarious and must imperatively be kept in a shoal.

Who can live with the Black tetra?

It lives very well with larger species provided they are peaceful (like the Scalar for example). On the other hand, for smaller species, do not go below 4 cm (1.5 inches) because it could stress them.

Note that it can also be a source of stress for calmer and shy fish. It has the reputation of being a fin nibbler.

However, this behavior only appears if the Tetra is kept in too small numbers. In a sufficient group, disputes usually remain internal to the species. To avoid any problem, it is nevertheless advisable to avoid the cohabitation with the sailfish like the Guppy or the Fighters. Also note that its vivid nature can easily intimidate the Corydoras.

You can associate them with other Tetras, Danios or Rasboras.

Breeding

How to breed the Black tetra?

With some knowledge, breeding of this species is possible. Spawning is done in pairs or in groups. Place in a spawning tank (50 L / 11 imp gal / 13 US gal) equipped with a protective grid and java mousse, a couple or a group. Temperature 24°C or 75°F and pH at 6.5/7. You can first separate males from females and stimulate breeding by feeding many individuals with live or frozen prey. Females are very prolific.

After spawning, remove the parents and lower the water height to 10 cm (4 inches), to gradually raise it when the fry will grow. Also keep this aquarium in complete darkness until hatching occurs after 20/24h. The development of fry is quite fast.